Don't know the difference between clown-dancing and krumping? David LaChapelle's gleeful celebration of a new dance phenomenon flourishing in LA - kicked off by reformed drug-dealer Tommy The Clown - should clear things up. The flailing physicality of Tommy's reinvention inspired his homies to turn away from gangbanging and form their own breakdance-style crews, creating frenzied routines to the accompanying clatter and pound of hardcore hip-hop. LaChapelle lovingly captures the performers' explosive, expressive movements and their ritualised competitions, with a (barely believable) disclaimer stressing that none of the footage is speeded up. Rize is also sharp on the social context to this sub-cultural ingenuity, convincingly arguing that krumping is a poetic act of resistance to the poverty and violence bedevilling the dancers' everyday lives.